Sink apparatus and related methods

ABSTRACT

The present invention provides a ventilated sink apparatus for reducing the amount of airborne contaminants escaping into the surrounding atmosphere from the sink basin and a method of used thereof.

PRIORITY CLAIM

The present non-provisional patent application claims priority under 35USC §119(e) from U.S. Provisional Patent Application having Ser. No.60/509,211, filed on Oct. 7, 2003, by Rothney et al. and titledVENTILATED SINK, wherein said provisional patent application is commonlyowned by the assignee of the present patent application and wherein theentire contents of said provisional patent application is incorporatedherein by reference.

FIELD OF THE INVENTION

The present invention relates generally to the field of sink structuresthat promote occupational and/or personal health, and more specifically,to a ventilated sink apparatus for reducing the amount of airbornecontaminants escaping from a sink basin into the surrounding atmospherefrom the sink basin, and a method of use thereof.

BACKGROUND OF THE INVENTION

Many laboratory, other industrial, commercial, and/or home-basedactivities carried out at a sink may generate undesirable airbornecontaminants (e.g., vapors, gases, fine particles, etc.). These can haveunpleasant odors or other irritating effects. Some can be physicallyand/or environmentally harmful, either to the surrounding physical plantand/or to personnel working at the sink. These effects can occur, forinstance, when leaving containers open that have volatile or fineparticulate contents, when preparing food items, when mixing volatileand/or particulate ingredients, when using cleaning compositions toclean items from the kitchen or lab, etc.

One illustrative context in which airborne contaminants can be generatedoccurs when cleaning and drying labware. Existing analytical methodologyconstraints in commercial and laboratory venues sometimes exclude theuse of dishwashers and other automated labware cleaning systems.Therefore, labware cleaning may be performed manually at a sink. Typicallabware cleaning steps include initial solvent wash or soak, cleaningand rinsing using water and optionally an adjuvant such as soap or thelike, and a final solvent rinse with acetone or the like to dry thelabware.

Acetone, a common drying solvent used for this purpose, has an ACGIH(American Conference of Governmental Industrial Hygienists) thresholdlimit value (TLV) of 500 ppm 8-hour time-weighted average and 750 ppm15-minute short-term exposure limit. Airborne acetone levels may exceedthese thresholds in some instances. Exposure monitoring during glasswarecleaning and chemical dispensing or transfer would indicate thatairborne concentrations of solvents, for example, acetone, may exceedoccupational exposure limits (OELs). Factors that contribute to elevatedairborne concentrations include lack of local exhaust ventilation,limited air circulation near sink areas, poor sink drainage, and use ofhot water.

OSHA's hierarchy of regulations requires that feasible engineeringcontrols are the preferred method of compliance for protecting employeesfrom airborne contaminants and are to be implemented first. Variousengineering controls to protect against airborne contaminants have beensuggested for sink-based activities. Using a sink inside a fume hood canreduce the amount of airborne contaminants released into the surroundingatmosphere. This is not always desirable, practical, economic, orefficient in terms of carrying out lab activities and/or using labspace. Fume hood countertops tend to be a place where chemicals aremixed, reacted, and spilled. The resultant soiled surfaces inside a fumehood are not the most desirable place in which to carry out labwarecleaning. Cleaning the fume hood area to carry out frequent labwarecleaning can disrupt working time, and it can be too expensive todedicate a fume hood just for cleaning operations. In a busy laboratoryfacility, there may also be a shortage of fume hoods relative to theamount of sink-based operations that could benefit from airbornecontaminant protection.

Countertop systems with, e.g., a side draw exhaust, mounted near a sinkin some fashion on the countertop are known. One significant drawback toa countertop system, e.g., traditional side-draw system, is that theexhaust ventilation is not integrally combined with the sink but isancillary thereto. Many still suffer from the potential for solventvapors to move across the breathing zone. Other issues include the lossof countertop space and the esthetically displeasing aspects of thesystem.

Therefore, there is a need to provide effective, economical protectionagainst airborne contamination when working at the sink industrially(e.g., a laboratory or manufacturing facility), commercially (e.g., arestaurant or the like), or at home in the kitchen or workshop, etc. Thedemand is especially keen with respect to protection againstoccupational exposure to airborne contaminants.

SUMMARY OF THE INVENTION

The present invention provides an apparatus and methods for reducing theamount of airborne contaminants escaping into the surrounding atmospherefrom a sink area during sink-based operations. The invention iseconomical for new sink installations and may be easily retrofit ontoexisting sink set-ups. The invention also eliminates the need for bulkylocal exhaust hoods while preserving work space.

The present invention generally relates to a ventilated sink thatintegrates ventilation and drainage capabilities into a singleapparatus, permitting effective protection against airborne contaminantsthat may be gaseous, vapor, particulate, or the like.

The present invention is applicable to a wide variety of sink-basedoperations, including food and chemical preparation or mixing, chemicalsynthesis, cleaning operations, container storage, sensitive itemhandling, etc. The present invention is particularly useful for labware,dishware, etc. washing operations utilizing solvents as well as duringchemical transfer and mixing, but is not intended to be limited to theseuses.

The methodologies according to the present invention are suitable forreducing, and potentially substantially eliminating, airbornecontaminant exposure during sink-based operations. This apparatus andmethod are improved, at least in one respect, compared to thosecurrently used by those skilled in the art in that the safety of aairborne contaminant hood may be combined with the convenience of asink, but without the confines and expense of a hood. Other features andadvantages of the present invention will become apparent from thefollowing detailed description, taken in conjunction with theaccompanying figures that illustrate by way of example the principles ofthe instant invention. According to one aspect of the present invention,a sink apparatus includes: a sink basin; at least one exhaust apertureprovided in the sink basin; and one or more exhaust pathways coupled tothe at least one exhaust aperture such that an exhaust can flow from thesink basin into the one or more exhaust pathways via the at least oneexhaust aperture.

According to another aspect of the present invention, a method ofventilating a sink includes the steps of: (1) providing a sink apparatusincluding: a sink basin; at least one exhaust aperture provided in thesink basin; and one or more exhaust pathways coupled to the at least oneexhaust aperture such that an exhaust can flow from the sink basin intothe one or more exhaust pathways via the at least one exhaust aperture;(2) and causing an exhaust to flow from the sink basin into the one ormore exhaust pathways via the at least one exhaust aperture. Preferably,the method includes the step of performing a sink-based activity in thesink basin while the exhaust is flowing.

According to another aspect of the present invention, a sink apparatusincludes: a sink basin; and at least a portion of an exhaust pathwayextending through a portion of the sink basin in a manner effective tohelp reduce airborne contamination in a sink area.

According to another aspect of the present invention, a method ofreducing airborne contamination in a sink area that includes a sinkbasin includes the step of causing an exhaust to protectively flow fromthe sink basin into an exhaust pathway in a manner that helps reduceexposure to airborne contaminants generated in the sink basin, whereinthe exhaust pathway comprises one or more exhaust apertures coupled tothe sink basin.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a sink area in which one embodiment of aventilated sink apparatus of the invention is installed, showing sectionplanes A-A and B-B.

FIG. 2 is an isometric, schematic view of one embodiment of a ventilatedsink basin of the present invention that is incorporated into the sinkapparatus shown in FIG. 1;

FIG. 3 is an isometric, schematic view of one embodiment of a plenumenclosure unit of the present invention that is incorporated into thesink apparatus shown in FIG. 1.

FIG. 4 is a cross-sectional view of the sink area of FIG. 1 taken alongthe plane A-A.

FIG. 5 is a cross-sectional view of the sink area of FIG. 1 taken alongthe plane B-B.

DETAILED DESCRIPTION OF THE INVENTION

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the invention as claimed. The presentinvention is described with regard to the accompanying drawings whichassist in illustrating various features of the invention. In thisregard, the present invention generally relates to an apparatus and amethod for reducing airborne contaminants from escaping into thesurrounding atmosphere during sink-based operations. In particular, thepresent invention relates to a ventilated sink apparatus and a method ofuse thereof. It is recognized by those skilled in the art thatprevention of exposure to airborne contaminants from a broad range ofchemicals and chemical related operations may be performed in accordancewith the present invention.

The following definitions will be helpful in understanding thespecification and claims. The definitions provide herein should be bornein mind when these terms are used in the following examples andthroughout the instant application.

As used herein, the term “airborne contaminant” includes, for example,one or more of a liquid, gas, vapor, air-borne particles, or the like.In labware cleaning operations, the contaminant typically is a liquid,vapor or gas. When mixing fine powders into other chemicals, thecontaminant typically will include airborne powder and perhaps liquidsplashes and/or airborne vapor from the chemicals.

The present invention relates to the prevention of exposure to airbornecontaminants during sink-based operations (e.g., labware and dishwarewashing, chemical transfer and the like) via an exhaust ventilationsystem local to the sink in which such operations are performed. Inpreferred embodiments, the exhaust ventilation system provides an airflow barrier over the sink basin opening, helping to prevent airbornecontaminants from escaping into the surrounding atmosphere, whileallowing clear and easy access to the sink basin area.

An illustrative embodiment of a sink area 10 incorporating a preferredventilated sink apparatus 12 of the present invention is generallyillustrated in FIGS. 1 through 5, which are provided for the purpose ofillustrating the practice of the present invention and which do notconstitute limitations on the scope thereof. For the purpose ofillustration, unless otherwise stated, the following description isdirected to an embodiment which is used in either laboratory ormanufacturing venues. This specificity is not meant to exclude the useof said sink configuration from use in household or other industrial orcommercial venues, each of which are envisioned in conjunction with theinstant invention.

Sink area 10 generally includes cabinet 14 including countertop 16 andcabinet front 18. Countertop 16 includes countertop cutout 20 to provideegress to sink basin interior 22 of the sink apparatus 12 mounted belowthe countertop 16. Faucet 24 is mounted in conventional fashion behindcountertop cutout 20, with its threaded faucet end 26 and faucetmounting hardware 28 being on the underside of countertop 16 (see FIG.4).

Sink apparatus 12 generally includes a sink basin 32 and an exhaustplenum housing 50 mounted around the outer, top periphery of sink basin32. One aspect of the present invention provides a sink apparatus havinga sink basin that has at least one wall coupling a sink rim to a sinkbottom. Usually one wall is used if the sink basin is cylindrical oroval, etc.; otherwise a plurality of walls are used if the sink isgenerally rectilinear or the like. Although shown as generallyrectilinear, it also is appreciated that can be configured to be usedwith a variety of other sizes and shapes depending upon factorsincluding the desired end use and the nature of the sink area beingused. Sink basin 32 includes sidewalls 34, front wall 36, and back wall38. The preferred size and shape as shown are those of standardlaboratory bench sinks, however, the size may be scaled up or down,accordingly and the basic shape may be altered in any number of ways,e.g., oval, triangle, parallelogram, trapezoid.

Sink basin 32 also includes bottom 40 having a sink drain 41. Top rim 44of sink basin 32 defines a sink opening 42 substantially registered withcountertop cutout 20.

One or more exhaust vents are provided in the one or more sink basinwalls proximal to the sink basin top rim, generally above the highestlevel to which the sink would be filled with liquid. The exhaust ventsmay be distributed substantially uniformly around the perimeter of theentire sink basin, as this facilitates generating what is, in practicaleffect, an effective airflow barrier over the sink basin, helping toisolate the basin from the ambient area near the sink. Uniquely, sinkbasin 32 is provided with a plurality of exhaust apertures 46 preferablydistributed around the periphery of sink basin as defined by walls 34,36, and 38 proximal to top rim 44. Exhaust apertures 46 may be of anyconvenient size and shape, but are shown (e.g., FIG. 5) for illustrativepurposes as elongated slot openings having a width of one inch betweenedges 47 and 49. The preferred peripheral distribution of exhaustapertures 46 helps to provide a uniform exhaust flow over the top of thesink when the exhaust system (not shown) functionality is engaged tosink apparatus 12. Generally, the exhaust apertures 46 would be situatedon the sink basin walls high enough to be above the highest anticipatedlevel of liquid to be held in the sink basin 32. In FIG. 5, edge 47 ofexhaust aperture 46 is located 1.5 inches from top rim 44. However, justin case liquid were to overflow into the exhaust plenum system throughapertures 46, the exhaust system, described further below, is fittedwith one or more liquid drains 68.

Sink basin 32 is mounted to the underside of countertop 16 in anysuitable way using conventional techniques now or hereafter developed.To drain liquid from sink basin 32, suitable plumbing (not shown) isfitted to sink drain 41. Note how the walls 34, 36, and 38 generallytaper inward from the top rim 44 down to bottom 40. This facilitatesfitting exhaust plenum housing 50 over sink basin 32 duringinstallation, as described further below.

Exhaust plenum housing 50 includes sidewalls 52, front wall 54, backwall56, and floor 60. Backwall 56 includes notch 58 to provide room forthreaded faucet end 26 and its mounting hardware 28. Floor 60 includescutout 62 defined by perimeter 61 that is sized to fit closely aroundsink basin 32. Housing 50 fits easily over the bottom of basin 32, butthen the fit between the two components becomes relatively closer ashousing 50 is slid upward to its installation position just undercountertop 16 near the top of basin 32.

Preferred embodiments may include one or more additional, desiredfeatures. As mentioned above, the exhaust plenum may incorporate one ormore liquid drains just in case liquid from the sink basin overflowsinto the plenum. The exhaust plenum optionally may incorporatereplaceable or reusable filter media for absorbing/adsorbing airbornecontaminants from the exhaust flow.

Mounting flange(s) 64 extends at least partially, but preferablysubstantially entirely as shown, around the top periphery of walls 52,54, and 56 of exhaust plenum housing 50 and are used to help installexhaust plenum housing 50 to the underside of countertop 16 after sinkbasin 32 is installed. A bead of caulk is applied onto the top surfaceof flange 64, and then housing 50 is fit over sink basin 32 to abut theunderside of countertop 16. Suitable mechanical means (not shown) suchas screws, brackets, nails, or the like may be used to secure housing 50into position. To help provide an airtight seal at joint 72, a bead ofcaulk 74 may be used. Thus, exhaust plenum housing 50 fits around thetop periphery of sink basin 32 with the bottom portion of basin 32projecting through cutout 62.

Preferably, the exhaust vent(s) are coupled to one or more exhaustplenums exterior to the sink basin. The plenum(s) may be hooked up to anexisting exhaust system or to stand-alone unit/componentry. Once housing50 is in position, an exhaust plenum 70 is thereby formed betweenhousing 50 and sink basin 32. The plenum 70 is defined at least in partby the spacing between walls 52, 54, and 56 on the outer side of theplenum 70 and walls 34, 36, and 38 on the inside of the plenum 70. Theplenum 70 in this preferred embodiment extends substantially around theentire periphery of sink basin 32, which helps to establish an even flowof exhaust into plenum 70 from the interior of sink basin 32 throughexhaust apertures 46.

Exhaust thus enters plenum 70 through apertures 46 and exits plenum 70through exhaust ports 66. Exhaust ports 66 may be further ducted toother exhaust lines (not shown) as desired. The sink apparatus 12 may becustom made to fit a space, or alternatively, be produced to accommodateexisting fixtures and plumbing enabling retro-fitting thereof.

The sink system of the present invention reduces the potential forairborne contaminants to cross the breathing zone and also minimizes theloss of countertop space. Such ventilated sinks as described in thepresent invention are effective at containing airborne solventconcentrations well below OELs for many operations. Thus, the goal ofprotecting personnel engaged in glassware cleansing and/or chemicaltransfer may be achieved and provides continued alignment withcommitments of providing a workplace free of recognized health hazards.

At least the surfaces, and preferably the bulk of the ventilated sinkapparatus 12 are fabricated from one or more materials that areresistant to chemical substances within the scope of intended use ofapparatus 12. A variety of materials may be used and include, forexample, granite, marble, stainless steel, ceramic, composite,fluoropolymer or other non-reactive polymers with respect to theintended use (epoxy resin, for instance), iron and porcelaincombinations, combinations of these, and mixtures thereof. For lab orindustrial applications, the preferred material is chemically stable,heat and cold resistant, acid and base resistant, and rigid and sturdy.Furthermore, it may be formulated to include additives to inhibit UVdamage and prevent splitting, splintering and cracking, as well aspossess fire retardant properties. Other desirable additives includeantioxidants, fungicides, bactericides, antistatic agents, inorganic ororganic fillers, and the like. Desirably, the apparatus made accordingto the instant invention has an acceptably long service life and isdurable for its intended use.

In use, an exhaust is drawn through these vents to help withdrawcontaminants generated in the sink basin. Airborne contaminants arisinginside the sink basin will have a tendency to be pulled into the exhaustsystem of the sink, significantly reducing the amount of airbornecontaminants that otherwise might be released into the ambient area nearthe sink. The airflow establishes a physical barrier to guidecontaminants into the exhaust plenum while keeping airborne contaminantsout of the ambient area near the sink, yet personnel may still easilyaccess the sink interior without obstruction. Sink-based operations maythen be carried out under the protection offered by the resultantairflow. In operation, the exhaust plenum 70 of ventilated sinkapparatus 12 is ducted to an appropriate exhaust system (not shown) byfitting additional exhaust lines to exhaust ports 66. The exhaust systemmay be one of continuous operation or electrically interfaced with thesink apparatus 12 via a standard on/off switch. When the exhaust systemis properly attached and engaged, it creates a continuous flow of airfrom the ambient area near the sink into the sink basin 32 viacountertop cutout 20 and sink opening 42. This flow then proceedsgenerally outward over the top of sink basin 32 through the exhaustapertures 46 and into plenum 70. From there, the flow is exhaustedthrough ports 66. Airborne contaminants generated in sink basin 32 tendto rise upward and get pulled into and carried away by the exhaust flow.In this manner, the tendency of airborne contaminants to rise above sinkbasin 32 and escape into the ambient area near the sink is dramaticallyreduced.

The rate of desired airflow drawn into the plenum 70 may vary over awide range. However, if it is too slow, the protection offered by theflow may be less than desired. If too fast, the air inside the sinkbasin 32 may be too turbulent. Balancing such concerns one recommendedoperating condition found to provide excellent protectioncharacteristics involves operating at a volumetric flow rate, Q, of 120ft³/min, where Q is given by Q=A*V, where A is the area (ft²) of thesink opening 42 and V is the velocity (ft/min) of the air moving throughthe sink opening 42. This condition would be suitable, for instance,when V is about 60 ft/min and the sink opening area is about 2 ft². Thetotal area of the exhaust apertures 46 desirably would be sufficient toprovide an air flow velocity through these of about 225 ft/min.

The instant invention provides a simple, integrated, ventilated sinkapparatus and method of use thereof. By incorporating an air barrierover a sink basin, exposure to chemical substances from inside the basinis limited and may be substantially eliminated. This sink apparatus andmethod do not require costly and sophisticated equipment or speciallytrained personnel, and reduces exposure health hazards.

Sink apparatus 12 shown in the Figures has a single sink basin 32. Theprinciples of the present invention may also be used for sinks withmultiple basins. For example, consider a typical kitchen sink with twobasins, in which each basin is separated by a dividing wall.Incorporating principles of the invention into such embodiments, one ormore basins may be fitted with exhaust apertures leading to an exhaustplenum as desired. To facilitate protective transfer of items from onebasin to the other, the dividing wall between basins may be relativelylower than the peripheral sink walls, thus helping to ensure that itemsremain below the sink rim periphery during transfer. Exhaust aperturesmay also be provided in the dividing wall to enhance protection. Whilethe above description contains many specificities, these should not beconstrued as limitations on the scope of the invention, but rather anexemplification of the preferred embodiment thereof. The presentinvention, in various embodiments, includes components, methods,processes, systems and/or apparatus substantially as depicted anddescribed herein, including various embodiments, subcombinations, andsubsets thereof. Many other variations are possible. Those of skill inthe art will understand how to make and use the present invention afterunderstanding the present disclosure. The present invention, in variousembodiments includes providing devices and methods in the absence ofitems not depicted and/or described herein or in various embodimentshereof, including in the absence of such items as may have been used inprevious devices or processes, e.g., for improving performance,achieving ease and/or reducing cost of implementation. The foregoingdiscussion of the invention has been presented for purposes ofillustration and description. The foregoing is not intended to limit theinvention to the form or forms disclosed herein. Although thedescription of the invention has included description of one or moreembodiments and certain variations and modification, other variationsand modification are within the scope of the invention, e.g., as may bewithin the skill and knowledge of those in the art, after understandingthe present disclosure. It is intended to obtain rights which includealternative embodiments to the extent permitted, including alternate,interchangeable and/or equivalent structures, functions, ranges or stepsto those claimed, whether or not such alternate, interchangeable and/orequivalent structures, functions, ranges or steps are disclosed herein,and without intending to publicly dedicate any patentable subjectmatter. Thus, the scope of the invention should be determined by theappended claims and their legal equivalents, rather than by examplesprovided herein.

1. A sink apparatus, comprising: a sink basin; at least one exhaustaperture provided in the sink basin; and one or more exhaust pathwayscoupled to the at least one exhaust aperture such that an exhaust canflow from the sink basin into the one or more exhaust pathways via theat least one exhaust aperture.
 2. The sink apparatus of claim 1, whereinthe sink basin comprises a sink basin interior and at least one wallwith a top rim and wherein the one or more exhaust pathways comprises anexhaust plenum positioned around at least a portion of the periphery ofthe sink basin, wherein the exhaust plenum is in fluid communicationwith the sink basin interior at least through said at least one exhaustaperture.
 3. The sink apparatus of claim 2, wherein the exhaust plenumfurther comprises at least one liquid overflow drain.
 4. The sinkapparatus of claim 2, wherein the apparatus comprises a plurality ofslot-shaped exhaust apertures provided around a periphery of the atleast one sink basin wall proximal to the top rim of the at least onesink basin wall.
 5. A method of ventilating a sink, comprising the stepsof: providing the sink apparatus of claim 1; and causing an exhaust toflow from the sink basin into the one or more exhaust pathways via theat least one exhaust aperture.
 6. The method of claim 5, furthercomprising the step of performing a sink-based activity in the sinkbasin while the exhaust is flowing.
 7. A method of ventilating a sink,comprising the steps of: providing the sink apparatus of claim 2; andcausing an exhaust to flow from the sink basin into the one or moreexhaust pathways via the at least one exhaust aperture.
 8. The method ofclaim 7, further comprising the step of performing a sink-based activityin the sink basin while the exhaust is flowing.
 9. A method ofventilating a sink, comprising the steps of: providing the sinkapparatus of claim 3; and causing an exhaust to flow from the sink basininto the one or more exhaust pathways via the at least one exhaustaperture.
 10. The method of claim 9, further comprising the step ofperforming a sink-based activity in the sink basin while the exhaust isflowing.
 11. A method of ventilating a sink, comprising the steps of:providing the sink apparatus of claim 4; and causing an exhaust to flowfrom the sink basin into the one or more exhaust pathways via the atleast one exhaust aperture.
 12. The method of claim 1 1, furthercomprising the step of performing a sink-based activity in the sinkbasin while the exhaust is flowing.
 13. A sink apparatus, comprising: asink basin; and at least a portion of an exhaust pathway extendingthrough a portion of the sink basin in a manner effective to help reduceairborne contamination in a sink area.
 14. A method of reducing airbornecontamination in a sink area comprising a sink basin, comprising thestep of causing an exhaust to protectively flow from the sink basin intoan exhaust pathway in a manner that helps reduce exposure to airbornecontaminants generated in the sink basin, wherein the exhaust pathwaycomprises one or more exhaust apertures coupled to the sink basin. 15.The method of claim 14, wherein the exhaust helps to establish aphysical barrier to help guide contaminants from the sink basin into theexhaust flow, thereby helping to reduce exposure to the contaminantsthat might otherwise occur in the absence of the exhaust flow.